@media (max-width: 1199px) and (min-width: 769px){
    .course-board{
        width: 100%;
        margin:0;
    }
}
@media (max-width:768px){
    
    .header .logo{
       
        color:red;
    }
    .header .nav-list{
        display:none;
        background-color: #333;
        width: 100%;
        margin:0;
        position: absolute;
        top:5rem;
        left:0;
        z-index: 1;

        flex-direction: column;
    }
    .header .nav-item{
        width:100%;
        text-align: center;
    }
    .header .nav-item:hover{
       background-color: #000;
       color:#fff;
    }
    .header .nav-lk{
        font-size: 1.4rem;
        line-height: 3rem;
    }
    .header .fa-bars{
        display: inline-block;
    }

    .course-board{
        width: 100%;
        margin:0;
        flex-wrap: wrap;
    }
    .course-board .course-card{
        width: 50%;
    }
    .course-board .course-card h1{
        font-size: 1.2rem;
    }
}